At 0927 GMT the LHC's online logbook records a quench in accelerator sector 3-4, the area between the Alice and CMS detectors. A tonne of liquid helium has leaked out of the system after an electrical junction at one of the electromagnets failed.

The log is noncommital:

"We're checking on it now."

A small team of technicians investigates the quench, after the sector is safely depressurized and allowed to warm up from absolute zero. They discover a curious, greenish luminous substance clinging to the long tubular corridor's polished concrete walls, and to the massive stainless steel conduit at its centre. It smells sickly sweet and simultaneously musky. At first gape, it appears, implausibly, to be biological in nature....